(1) Field of the Invention
The present invention relates to a blind nut setting tool, and particularly to a blind nut setting tool that can adjust a setting stroke of a blind nut.
(2) Summary of the Prior Art
Motor-driven tools for setting blind nuts have conventionally been known. These tools comprise a mandrel having a front end externally threaded with a pulling rod connected to the rear end of the mandrel and having an externally threaded rear portion. A nut member is screwed to the externally threaded portion of the pulling rod and there is means to rotate the nut member. A cylindrical mast housing extends from the tool body forwardly so as to enclose the nut member and a rear portion of the pulling rod. A cylindrical nose housing is screwed to the front end of the mast housing and extends from the mast housing forwardly so as to enclose the pulling rod and a rear portion of the mandrel. A nose portion encloses the mandrel with the external thread of the mandrel projected and adapted to be slidable in the axial direction of the nose housing but unrotatable to the nose housing. The mandrel is rotated by a rotation of the nut member so that the external thread at the front end of the mandrel is screwed into the blind nut. Subsequently the rotations of the mandrel and the pulling rod are stopped by a contact between a flange of the blind nut and a front end surface of the nose portion so that the tool body moves forwardly by a predetermined length relative to the nose portion. Then, the mandrel is retracted rearwardly by a predetermined stroke so as to expand a tubular portion of the blind nut to be set to a panel.
In such a blind nut setting tool, as described adjustment of a setting stroke is effected by adjusting a distance between the rear end surface of the flange of the nose piece of the nose portion and the front end surface of the nose housing by means of a nut. The stroke adjustment is also possible by moving the nose housing axially. However, such methods of adjustment require steps to measure the distance with a gauge or the like and to calculate a stroke corresponding to the distance, these steps being troublesome and quite time-consuming.